1. Field of the Invention
The present invention relates to a liquid ejection head for ejecting a liquid onto a printing medium and a manufacturing method for the liquid ejection head.
2. Description of the Related Art
One type of common printing apparatus is an inkjet printing apparatus that applies energy to ink contained in the energy application chambers of a print head, and ejects ink droplets through ejection ports.
A partial structure of an example print head employed for such an inkjet printing apparatus is disclosed in FIG. 9.
Another example print head for an inkjet printing apparatus is disclosed, for example, in Japanese Patent Laid-Open No. 2006-290000. The print head proposed in Japanese Patent Laid-Open No. 2006-290000 has nozzles in which the walls defining the energy application chambers are tapered so that the energy application chambers are narrowed as ejection ports are neared. Thus, since the energy application chambers narrow as they near the ejection ports, the resistance of ink is reduced as the ink transfers through the energy application chambers. Therefore, little energy is required to eject ink, and during printing, the ink ejection efficiency is improved.
Recently, print heads, for use in inkjet printing apparatuses, that can perform high-speed, high-quality printing, is strongly desired. In order to satisfy these requests, it is needed that the nozzles are arranged at much high densities. With a structure wherein nozzles are arranged at a high density, high resolution images can be printed that provide improved image quality. In addition, because of the structure of the print head of the inkjet printing apparatus, the increase in the nozzle density is available at a comparatively low cost.
In the print head disclosed in Japanese Patent Laid-Open No. 2006-290000, however, when the energy application chambers are narrowed as they approach ejection ports, the bottom faces of the energy application chambers, wherein printing elements are located, are comparatively wide. And generally, an orifice plate, in which ejection ports are formed, and a substrate, on which the printing elements are arranged, are adhered to each other, on the printing element formation faces of the energy application chambers, wherein the printing elements are located. Therefore, when the nozzles are arranged at a high density and the energy application chambers are tapered, the size of the area to which the substrate and the orifice plate, in which the ejection ports are formed, are adhered tends to be reduced, relative to the flow rate of a liquid that is supplied to the energy application chambers. Thus, essentially, the size of the area available for the adhesion of the orifice plate and the substrate is insufficient, and the possibility exists that these components will be separated from each other.